The proliferation of mobile devices with GPS capabilities has lead to the development of a multitude of applications that rely on a device's ability to determine its location. However the usefulness of these location based services is diminished when the user is within a building where GPS and data signals are attenuated or undetectable. This is especially problematic in large complex buildings such as shopping malls or hospitals where navigation can be very challenging and large dead zones frequently exist. Accordingly, there is need in the art for location based system for mobile devices for indoor use where there is limited GPS and data connectivity.